Spooling tension tester



FiQ- 4 4 Sept. 5, 1967 w. T. HANKINS, JR 3,339,406

7 V SPOOLING TENSION TESTER Filed Dec. 10, 1964 2 Sheets-Sheet J.

29 I Fig. 5

Sept. 5, 1967 w. T. HANKINS, JR 7 3,339,406

SPOOLING TENSION TESTER 2 Sheets-Sheet :3

Filed Dec. 10, 1964 Fig. 2

JNVENTOR. WILLIAM 1. HANKINS AGENT United States Patent 3,339,406 SPOOLING TENSION TESTER William T. Hankius, Jr., Albert Lea, Minu., assignor to Burroughs Corporation, Detroit, Mich, a corporation of Michigan Filed Dec. 10, 1964, Ser.No. 417,424 7 Claims. (Cl. 73-143) This invention relates to a spooling tension tester for ascertaining whether the tension of a spool of wound ink ribbon is within prescribed limits along with testing for the correct diameter of the ribboned spool. v

In modern automatic sorting and accounting operations, information is printed on documents such as checks and ledger sheets in magnetic ink in distorted alphanumeric type characters. Magnetic Ink Character Recognition (MICR) equipment converts the magnetic ink character into an electrical waveform which is interpreted by the logic section of the computing equipment. Each character generates a different waveform as it passes under a read head.

Since it is required that the magnetic ink character be readable, not only by the computing equipment but also by humans, the allowable diiferences permitted in their waveforms become critical. It is apparent that a smeared or improperly printed character, such as one without suflicient ink, could generate one waveform which could be erroneously interpreted by the computer as another.

Due to the close tolerances under which the total MICR equipment must operate, it is extremely important that each step in the overall process be very closely controlled.

One of the problems which has been encountered in the printing of magnetic characters is offsetting. Oifsetting may occur when a roll of ribbon is too tightly wound, thereby giving rise to a transfer or offsetting of the ink composition onto the backing layer of the adjacent turn on the wound ribbon. This results in a reduced amount of magnetic ink on the printing side of the ribbon and an excess amount on the backing layer. Utilization of this defective ribbon could result in the printing of characters which could be erroneously interpreted. In addition, since the ink composition is on the backing layer of the ribbon, it tends to adhere to the type face of the printer, causing an accelerated buildup of ink particles within the open areas of the type face. This buildup can cause a false distortion of the printed character, resulting in an erroneous interpretation by the computing equipment.

Conversely, when a ribbon which is too loosely wound is used in a printing mechanism, it tends to unwind while the ribbon spool itself remains stationary. This results not only in a ribbon feeding problem, but more importantly, in the relative movement or sliding between two adjacent turns of ribbon which can cause offsetting. Although from a different cause, the problems of this oifsetting are the same as hereinabove stated.

Heretofore only a rough approximation could be made as to whether a ribbon was wound on a spool with the proper amountof tension. It is apparent that extreme cases of tightness or looseness of the ribbon could be determined by a skilled ribbon tension tester without the aid of equipment. However, in evaluating marginal cases, the human error involved in normal inspection has been a significant problem resulting in unnecessary and costly rejection of good ribbon and/or acceptance of bad ribbon.

It is, therefore, an object of this invention to provide simple but accurate apparatus for the nondestructive testing of the spooling tension of ink ribbons.

It is a further object of this invention to provide simple apparatus for the nondestructive testing of a spool of ink ribbon to ascertain whether or not the quantity wrapped thereon is within tolerance.

lot:

In accordance with the foregoing objects, a preferred embodiment of the invention comprises transparent counterbored holding means with a hallow interior, for receiving a properly tensioned spool of ribbon therein against the counterbore, means for driving the spool into the hollow interior by predetermined force, and calibration means on said holding means for measuring the penetration of the coning of said ribbon into said hollow interior to determine if said tensioned spool of ribbon is within tolerance.

Other objects and feasures of the invention will be specifically pointed out or will become apparent when referring to the following description taken in conjunction with the accompanying drawings in which:

FIG. 1 depicts the counterbored holding means;

FIG. 2 is a pictorial representation of the invention;

FIG. 3 illustrates a properly tensioned ribbon under test;

FIG. 4 illustrates a too tightly tensioned ribbon under test; and

FIG. 5 illustrates a too loosely tensioned ribbon under test.

The preferred embodiment of the invention, as illus trated in FIGS. 1 and 2, comprises a substantially rigid base 11 and a transparent member or cylinder 13 mounted thereon having a hollowed interior portion 14 of rightcircular cylindrical shape and an upper opening 16. A guide rod 15 vertically mounted on circular base 17 rests on the rigid base 11 so that the longitudinal axes of the guide rod 15 and the hollow portion 14 of transparent member 13 are coincident. The diameter of circular base 17 is substantially the same as the inside diameter of hollow portion 14 of transparent member 13.

The transparent member 13 is counterbored at its upper opening 16 to provide an internal holding means or shoulder 19. At least one reference line 21 is scribed about the outer periphery of transparent member 13, parallel to and a predetermined distance below the shoulder 19.

As shown in FIG. 2, a spool 23 having a core 25 with a quantity of ribbon 27 wrapped thereon, is placed on vertical rod 15 with the outer periphery of spool 23 in frictional contact with the shoulder 19. A first predetermined weight 29, shaped substantially like an inverted, truncated, right circular cone, is placed on vertical guide rod 15 and in pressure contact with core 23 of spool 21. A properly tensioned spool of ribbon will not cone out or telescope below reference line 21. A spool of ribbon which is too loosely wound may cone out or extend below reference line 21, thereby being indicative that it should be rejected as unsatisfactory. In the event that spool 23 does not cone out below reference line 21, a second predetermined weight 31, substantially doughnut shaped, is placed over vertical rod 15 in contact with first weight 29 and coning out or telescoping is again observed relative to reference line 21.

It should be noted that for ribbons having different diameters and/or spooling tensions, the total weight and the time the weight is applied, may be variable. In the specific embodiment shown, the first weight 29 is a 10- ounce weight while the second weight 31 weighs 40 ounces. In order to insure uniformity of testing using these specific values, the combined weights 29 and 31 should remain in a pressure position no longer than 10 seconds.

As shown in FIG. 3, a properly tensioned spool of ribbon would cone out so that the apex of the cone is tangent with the reference line 21.

FIG. 4 is illustrative of the situation when a ribbon spool is wound with too great tension. As will be seen, this spool does not cone out to the reference mark 21, therefore it should be rejected. The spool as depicted in FIG. 5 is too loosely tensioned and extends below reference line 21 and should also be rejected.

In addition to the measurements hereinabove described, the invention may be utilized to ascertain roughly whether the proper amount of magnetic ink ribbon has been wound on a particular spool. Spool 23 is placed over vertical rod 15 and moved downwardly so that it is proximate the counterbore of shoulder 19. In the event that spool 21 will not enter the counterbored section, it is indicative that there is too much ribbon on the spool. On the other hand, if spool 23 does enter the counterbored section but continues its downward movement with its periphery fail ing to rest upon the shoulder 19, it is indicative that there is too little ribbon on the spool. In the event that the outer periphery of spool 23 rests on shoulder 19, it indicates that the amount of ribbon on the spool is approximately the proper amount.

While this invention has been described in the particular problems of magnetic ink ribbons, it is obvious that its utility is not limited to this environment. Any ribboned spools can be tested on applicants device.

While in this description only the preferred embodiment has been described, it should be noted that the scope of the invention does not exclude various other changes and modifications that are within the skill of those familiar with the art, the scope of the invention being limited only by the folowing claims.

I claim:

1. A nondestructive ribbon spool tension tester comprising a base,

a transparent member mounted on the base and having a hollow interior opening out through the upper end thereof,

means integral with the open end of said member for holding said ribbon spool by its outer edge,

guide means longitudinally coaxial with and inside said transparent member,

a plurality of removable weights slidably mounted on said guide means for applying pressure to said ribbon spool, and

at least one reference mark, scribed horizontally about the periphery of said transparent member for measuring the penetration of the coning of said ribbon into said open end of the member.

2. A ribbon spooling tension tester including, in combination,

means for engaging only the outer peripheral portion of one end of a spool of ribbon,

means for engaging only the inner peripheral portion of the other end of the spool of ribbon, the portion of the ribbon winding intermediate said outer and inner peripheral portions being free of engagement by said means,

means for applying a predetermined force to said engaging means while a spool of ribbon is so engaged thereby in a direction axially toward the spool to cause the turns of the ribbon on the spool to cone telescopically, and

means for indicating the extent of the coning of the ribbon turns.

3. A ribbon spooling tension tester comprising:

a first member shaped to engage only one end of the ribbon spool along its outer circumference.

a second member shaped to engage the other end of the ribbon only at its center portion, means for applying a predetermined force to said second member while the spool of ribbon is engaged between said first and second members, said predetermined force being applied to said second member axial to the engaged ribbon spool thereby causing the turns of the ribbon to cone telescopically, and

means for indicating the extent of the coning of the ribbon turns.

4. The device of claim 3 wherein said first member has one end bored and counterbored such that the diameter of the bore defines the minimum acceptable diameter of a ribbon spool placed on this end of said first member, and the diameter of said counterbore defines the maximum acceptable diameter of a ribbon spool placed therein.

5. The device of claim 4 including a guide rod for slidably receiving a ribbon spool and having its axis coaxial to that of said first and second members, and

base means for supporting said guide rod in upright position.

6. The device of claim 5 wherein said predetermined pressure means comprises at least one weight slidably mounted on said guide rod.

7. The device of claim 3 wherein said means for indicating the extent of the coning of the ribbon turns comprises a transpart portion on said first member and a reference mark scribed therein.

No references cited.

JAMES I GILL, Primary Examiner.

R. C. QUEISSER, Examiner. C. A. RUEHL, Assistant Examiner. 

1. A NONDESTRUCTIVE RIBBON SPOOL TENSION TESTER COMPRISING A BASE, A TRANSPARENT MEMBER MOUNTED ON THE BASE AND HAVING A HOLLOW INTERIOR OPENING OUT THROUGH THE UPPER END THEREOF, MEANS INTEGRAL WITH THE OPEN END OF SAID MEMBER FOR HOLDING SAID RIBBON SPOOL BY ITS OUTER EDGE, GUIDE MEANS LONGITUDINALLY COAXIAL WITH AND INSIDE SAID TRANSPARENT MEMBER, A PLURALITY OF REMOVABLE WEIGHTS SLIDABLY MOUNTED ON SAID GUIDE MEANS FOR APPLYING PRESSURE TO SAID RIBBON SPOOL, AND AT LEAST ONE REFERENCE MARK, SCRIBED HORIZONTALLY ABOUT THE PERIPHERY OF SAID TRANSPARENT MEMBER FOR MEASURING THE PENETRATION OF THE CONING OF SAID RIBBON INTO SAID OPEN END OF THE MEMBER. 